Electric switch.



No. 638,705. Patented Dec. l2, I899. J. l GREVELING.

ELECTRIC SWITCH.

licatio' (No Model.)

UNITED STATES PATENT QEEI cE.

JOHN L. OREVELING, OF NEW YORK, N. Y.

ELECTRIC SWITCH.

SPEGIFICATION forming part of Letters Patent No. 638,705, dated December12, 1899.

Application filed January 24, 1899. Serial No. 703,246. (No model.)

To aZZ whom, it may concern:

Be it known that I, JOHN L. CREVELING, of New York, in the county of NewYork, State of New York, have invented certain new and usefulImprovements in Electric Switches, of which the following is a completespecification, reference beinghad to the accompanying drawings.

The object of my invention is to produce an electric switch of compactform that is adapted to carry a current of comparatively high amperageand voltage.

Under certain conditions of use.-as, for example, in heating cars byelectricity-itis not only necessary to employ such a current, but it isalso of considerable practical importance to employ for such service aswitch that occupies but small space. In red ucing the size of theswitch it is necessary to make provision against arcing. This maybereadily accomplished by locating the poles a sufficient distance apart;but on account of the distance required between poles difficulty hasbeen experienced in practice in constructing a switch without making itbulky and cumbersome.

My invention therefore consists in locating the contacts of the switchupon opposite sides of an insulating-plate of suitable shape andthickness. By this means the contacts upon one side may be separated asufficient distance to prevent arcing between them, and theinterposition of a suitable insulatingplate prevents arcing betweencontacts or terminals upon opposite sides of the plate.

In the accompanying drawings, Figure I is a perspective view of myswitch complete. Fig. II is a top plan View of the same with the cap andbutton removed. Fig. III is a bottom plan View of the insulating-plateremoved from the base, showing the knives in the position they occupywhen the whole is assembled. Fig. IV is a side elevation of thesubject-matter of Fig. II. Fig. Vis a section on the line V V of Fig.III. Fig. VI is a perspective View of one of the intermediate contactsdetached.

Referring to the numerals on the drawings, 1 indicates a base ofsuitable insulating material, and 2 a protective cap or covering fittedover the flange 3 (see Fig. IV) of the base.

4 indicates an insulating-plate secured to but separated from the base.The means employed for securing the plate 4: to the base consist in theform of embodiment illustrated of the intermediate contact-studs 5,which are suitablyconstructed for the purpose. One of the intermediatestuds 5 is shown in Fig. VI, in which 7indicates a tube of conductivematerialas, for example, brass-provided with an intermediate flange 8,that is secured to the base 1, as by aid of screws 9. The tube 7 carriesspring contact-plates 10, suitably spaced, as by washers 11. The plate 1is secured to the tubes 7, as by screws 12, threaded into the end of thetube and having thei r heads countersunk in the plate 4..

In practice the heads of the screws 12 are covered with wax or othersuitable insulating material.

The ends of the tube 7 opposite that which carries the contact-platesextend through the base, and each is provided wit-h a transversebinding-screw 14: for wiring purposes.

The contact-studs 6 are similar to the contact-studs 5, consisting of atube 15, provided with a flange 16, that is secured to the plate 1, asby screws 17. The tube 15 carries spring contact-plates 18, suitablyspaced, as by washers 19. Each of the con tact-studs 6, however, has thetube 15 only on one side of the flange 16, the bore thereof registeringwith an aperture in the plate a, which communicates with an insulatingspacing-tube 21, communicating with an aperturein the base 1. By thismeans wires may be connected with the studs 6 from the back of the plate1, each tube 15 being provided with a binding-screw 22 for securing awire in place.

Centrally mounted upon the base 1 and within an aperture in the plate I,which is illustrated as an annular plate, is revolubly mounted aninsulating-hub 24, to the opposite ends of which are securedswitch-knives 25 and 26, that work between the contactplates 10 and 18,respectively, each knife being adapted to establish communicationbetween any two of the contacts with which it is adapted to engage. Theknives 25 and 20, being secured to the hub 24, bear a fixed relation oneto the other and in the illustrated form of embodiment of my inventionoperate together, being adapted to be manipulated, as by a button 27, onthe outside of the cap 2, detachably connected, as by a screw-stud 2t tothe hub 2-1.. That fcaturcof the device illustrated, however, as well asthe special mechanism for actuating the knives, constitutes no part ofmy invention and is neither illustrated nor described in detail.

The form of knife-actuating mechanism illustrated is substantially thesame as that commercially known as a Hart switch. It being well andfamiliarly known to all skilled in the art and constituting no part ofmyinvention does not appear to require detail de scription orillustration. Suffice it to say in this connection that the movement ofthe button 27 is adapted to impart to the knives a quick abrupt movementfrom one set of contacts to the next set in the order of movement.

My invention, as was previously specified in general terms, consists inthe employment of the members (which, for convenience of description, Ishall in the claims denominate contact-making members) represented bythe knives 25 and 26, that engage contacts upon opposite sides of aninsulating-plate, the contacts on one side being represented by themembers 5 and those upon the opposite side by the members (5.

In embodying my invention in practical form the contacts (3, forexample, being of any required number, are located at such dis-- tanceone from the other as will insure against arcing.

able by calculation of the forces employed. The contacts 5 are locatedupon the opposite sides of the insulating-plate 4, preferably at pointsmidway between adjacent contacts 6. Security from arcing between thecontacts 5 is therefore provided in the distance which Such distance-isreadily determin- I subscribed my name.

which separate one contact 5, for example,

from its next neighboring contact (5.

What I claim is- 1. In an electric switch, the combination with aninsulating-plate and a plurality of contacts arranged in series upon oneside of said plate, and separated, respectively, by such distances aswill insure against arcing, a plurality of contacts similarly separatedupon the opposite side of said plate, the individual contacts of theopposite sides being separated by approximately half the distance whichseparates the individuals of each series as well as by theinsulating-plate, of a plurality of contact-making members cooperating,respectively, with said contacts, substantially as set forth.

2. In an electric switch, the combination with aninsulating-l')ase,insulating-plates and tubular intermediatecontact-studs uniting the base and plate, of tubular outer contactstudscommunicating through insulating spacing-tubes with apertures in thebase, a

hub pivotally mounted in the base, and contact-1naking members upon thehub working upon opposite sides of the plate, as and 'for the purposespecified.

In testimony of all which I have hereunto JOHN L. CREVELING.

Witnesses:

ELMER E. ALLBEE, Row. C. SOFIO.

